Noxious bloom could close rivers for a year

The floods of January and February are still impacting on some north coast waterways.

A bloom of the aquatic noxious weed salvinia has moved through wetlands and into the Maria River at Kempsey.

The bloom could have a severe impact on native fish populations.

Port Macquarie-Hastings Council, the Kempsey Council and the Road and Maritime Services will place floating booms across Connection Creek upstream from its junction with the Maria River.

The floating bloom of salvinia poses a potential threat to the Maria, Hastings and Macleay ecosystems.

The council's Director of Development and Environmental Services Matt Rogers says the series of floating booms will keep the bloom trapped where it can be treated.

He says that part of Connection Creek near the Maria River junction will be closed to boats for some time.

"It could be months to years.

"It's one of those issues that you can't be sure of certainly in the early stages but the weed control will happen over years.

"How long that part of the creek is boomed off for is a bit hard to answer at this stage but we would probably have a better idea in the weeks to months ahead," he said.

The three flood events have been blamed for the bloom of salvinia, a noxious weed with the potential to do serious ecological damage.

Mr Rogers says once it has been isolated there are several ways to attack the weed.

"There's a number of ways of treating it but essentially it requires extreme vigilance on the part of the Weed Authorities and other people using the area whether they're boaties or landowners and a mixture of chemical, biological and physical control," he said.